Healthy men and women with blood pressure less than 140mm Hg systolic and less than 90mm Hg diastolic and cholesterol levels 200 to 240mg per dL.

Exclusion Criteria:

Substantial weight change in the previous six months

Taking medication known to affect blood pressure, lipids or glucose.

Description of Study Protocol:

Design

Non-randomized crossover trial.

Dietary Intake/Dietary Assessment Methodology

Subjects discontinued all vitamins and supplements and agreed to consume only those foods presented to them or approved by the investigators. All foods were prepared and weighed to the nearest 0.5g at the study facility.

Intervention

Subjects consumed the Step I American Heart Association (AHA) diet with a seven-day rotating menu for the first two weeks

The three diets listed below were consumed for five weeks each. An equal number of participants consumed each diet during each period and all subjects consumed all diets. Whole-grain diets contained 0 to 2.2g per 1,000kcal soluble fiber form barley and 9.7 to 11.9g per 1,000kcal total dietary fiber.

Barley

Whole wheat or brown rice

Half barley and half whole wheat or brown rice.

Statistical Analysis

Date were analyzed using mixed procedure analysis of variance

Subjects were their own controls.

Data Collection Summary:

Timing of Measurements

Weekly after breakfast, blood pressure was taken at the study facility

24-hour complete urine samples were collected during the last three days of each period.

Consumption of a healthy diet high in fiber from whole-grain foods lowers systolic and diastolic blood pressure in mildly hypercholesterolemic men and women whether sources are barley (soluble fiber), whole wheat and brown rice (insoluble fiber) or a combination of these whole-grain foods.

Reviewer Comments:

Study strengths:

24-hour complete urine samples were collected to assure that there was no variation in minerals or dietary factors that might affect blood pressure or indicate non-compliance. Mean mineral excretion did not vary by period

Duplicate blood pressure readings were taken

Study limitations:

Small sample size

Amount of participation in physical activity was not collected throughout the study, and subjects lost weight (about 1kg) during the study.

Research Design and Implementation Criteria Checklist: Primary Research

Relevance Questions

1.

Would implementing the studied intervention or procedure (if found successful) result in improved outcomes for the patients/clients/population group? (Not Applicable for some epidemiological studies)

Yes

2.

Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about?

Yes

3.

Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to nutrition or dietetics practice?

Yes

4.

Is the intervention or procedure feasible? (NA for some epidemiological studies)

Yes

Validity Questions

1.

Was the research question clearly stated?

Yes

1.1.

Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified?

Yes

1.2.

Was (were) the outcome(s) [dependent variable(s)] clearly indicated?

Yes

1.3.

Were the target population and setting specified?

Yes

2.

Was the selection of study subjects/patients free from bias?

Yes

2.1.

Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study?

Yes

2.2.

Were criteria applied equally to all study groups?

Yes

2.3.

Were health, demographics, and other characteristics of subjects described?

Yes

2.4.

Were the subjects/patients a representative sample of the relevant population?

???

3.

Were study groups comparable?

N/A

3.1.

Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT)

N/A

3.2.

Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline?

If cohort study or cross-sectional study, were groups comparable on important confounding factors and/or were preexisting differences accounted for by using appropriate adjustments in statistical analysis?

N/A

3.5.

If case control or cross-sectional study, were potential confounding factors comparable for cases and controls? (If case series or trial with subjects serving as own control, this criterion is not applicable. Criterion may not be applicable in some cross-sectional studies.)

N/A

3.6.

If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")?

N/A

4.

Was method of handling withdrawals described?

Yes

4.1.

Were follow-up methods described and the same for all groups?

Yes

4.2.

Was the number, characteristics of withdrawals (i.e., dropouts, lost to follow up, attrition rate) and/or response rate (cross-sectional studies) described for each group? (Follow up goal for a strong study is 80%.)

Yes

4.3.

Were all enrolled subjects/patients (in the original sample) accounted for?

Yes

4.4.

Were reasons for withdrawals similar across groups?

N/A

4.5.

If diagnostic test, was decision to perform reference test not dependent on results of test under study?

N/A

5.

Was blinding used to prevent introduction of bias?

???

5.1.

In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate?

???

5.2.

Were data collectors blinded for outcomes assessment? (If outcome is measured using an objective test, such as a lab value, this criterion is assumed to be met.)

???

5.3.

In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded?

N/A

5.4.

In case control study, was case definition explicit and case ascertainment not influenced by exposure status?

N/A

5.5.

In diagnostic study, were test results blinded to patient history and other test results?

N/A

6.

Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors described?

Yes

6.1.

In RCT or other intervention trial, were protocols described for all regimens studied?

Yes

6.2.

In observational study, were interventions, study settings, and clinicians/provider described?

N/A

6.3.

Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect?

???

6.4.

Was the amount of exposure and, if relevant, subject/patient compliance measured?